Underlying Causes and Therapeutic Targeting of the Inflammatory Tumor Microenvironment

Historically, the link between chronic inflammation and cancer has long been speculated. Only more recently, pre-clinical and epidemiologic data as well as clinical evidence all point to the role of the tumor microenvironment as inextricably connected to the neoplastic process. The tumor microenvironment (TME), a complex mix of vasculature, inflammatory cells, and stromal cells is the essential "soil" helping to modulate tumor potential. Increasingly, evidence suggests that chronic inflammation modifies the tumor microenvironment, via a host of mechanisms, including the production of cytokines, pro-inflammatory mediators, angiogenesis, and tissue remodeling. Inflammation can be triggered by a variety of different pressures, such as carcinogen exposure, immune dysfunction, dietary habits, and obesity, as well as genetic alterations leading to oncogene activation or loss of tumor suppressors. In this review, we examine the concept of the tumor microenvironment as related to both extrinsic and intrinsic stimuli that promote chronic inflammation and in turn tumorigenesis. Understanding the common pathways inherent in an inflammatory response and the tumor microenvironment may shed light on new therapies for both primary and metastatic disease. The concept of personalized medicine has pushed the field of oncology to drill down on the genetic changes of a cancer, in the hopes of identifying individually targeted agents. Given the complexities of the tumor microenvironment, it is clear that effective oncologic therapies will necessitate targeting not only the cancer cells, but their dynamic relationship to the tumor microenvironment as well.

MABp1 for the treatment of colorectal cancer

INTRODUCTION

Inflammation is an established process in colorectal cancer development and a hallmark of progression, and pro-inflammatory cytokines have been implicated in the morbidity and functional compromise associated with malignancy. MABp1, described as a first-in-class true human antibody against interleukin-1α, has undergone clinical trial evaluation in a number of indications, recently completing late phase clinical trial testing under Fast Track designation for cancer anorexia-cachexia syndrome in colorectal cancer patients. To date, MABp1 has been evaluated as a novel therapeutic strategy to ameliorate phenotypic factors associated with poor prognosis in colorectal cancer patients. Areas covered: In this review, the authors discuss the clinical trial data available to date for this antibody in colorectal cancer, including novel clinical trial endpoints utilized to evaluate sarcopenia and inflammation, as well as the proposed role of interleukin-1α antagonism in leading to improved patient outcomes. Expert opinion: There is a multitude of antibodies in therapeutic development in oncology, and MABp1 is a novel class of antibody which has been safely tolerated to date. Clinical studies of this agent suggest a significant improvement in lean body mass, though additional results evaluating the impact of targeting inflammation as a strategy to delay disease progression in this population are awaited.